What is the diet for small bowel overgrowth? A comprehensive guide

January 8, 2026 •

4 min read

According to a 2022 research review, while diets cannot cure SIBO alone, they can effectively reduce symptoms for many sufferers. If you have been diagnosed with small bowel overgrowth, also known as SIBO, adjusting your diet is a key strategy for managing discomfort and supporting recovery.

Quick Summary

A diet for small bowel overgrowth involves limiting fermentable carbohydrates (FODMAPs) to reduce bacterial fuel, managing symptoms, and promoting healing. Key strategies include low FODMAP and, in some cases, an elemental diet, alongside careful reintroduction to identify triggers and create a sustainable eating plan.

Key Points

Reduce Fermentable Carbohydrates: Restrict foods high in FODMAPs (Fermentable Oligosaccharides, Disaccharides, Monosaccharides, and Polyols) to reduce the fuel for overgrown bacteria.
Consider an Elemental Diet for Severe Cases: A liquid-only diet of predigested nutrients can be used under medical supervision to starve gut bacteria effectively.
Follow an Elimination and Reintroduction Protocol: Start with a restrictive diet, then slowly reintroduce foods to identify your specific triggers and personalize your long-term plan.
Focus on Digestible Foods: Choose lean proteins, healthy fats, and low-FODMAP fruits and vegetables to support recovery without exacerbating symptoms.
Implement Mindful Eating Practices: Practice meal spacing and thorough chewing to aid digestion and promote the gut's natural "housecleaning" mechanism.
Manage Stress and Hydration: Stress can worsen gut issues, so incorporating relaxation techniques is important. Adequate hydration is also crucial for healthy digestion.
Work with a Healthcare Professional: Since SIBO is highly individual, partnering with a doctor or dietitian ensures a safe and nutritionally balanced treatment approach.

Understanding the Goals of a SIBO Diet

Small intestinal bacterial overgrowth (SIBO) occurs when there is an abnormal increase in the bacterial population in the small intestine. These bacteria feed on and ferment undigested food, primarily carbohydrates, producing excess gases (hydrogen and methane) that lead to uncomfortable symptoms like bloating, abdominal pain, and diarrhea or constipation. A SIBO diet is not a cure but a therapeutic tool designed to reduce these symptoms and starve the overgrowing bacteria by limiting their food source. The primary goal is to provide relief and create a favorable environment for gut healing, often used in conjunction with antibiotic or herbal treatments.

The Low-FODMAP Diet

The low-FODMAP diet is one of the most widely recommended approaches for managing SIBO symptoms, although research specifically for SIBO is limited compared to its use for IBS. FODMAP stands for Fermentable Oligosaccharides, Disaccharides, Monosaccharides, And Polyols. These are short-chain carbohydrates that are poorly absorbed and highly fermentable. By temporarily restricting foods high in FODMAPs, you can significantly reduce the fuel available for the overgrown bacteria.

Phase 1: Elimination This initial phase, lasting typically two to six weeks, involves strictly avoiding high-FODMAP foods. This includes many common items like onions, garlic, apples, pears, beans, and certain dairy products. The aim is to achieve a significant reduction in symptoms.

Phase 2: Reintroduction After the elimination phase, you work with a dietitian to reintroduce eliminated food groups systematically. This helps you identify which specific FODMAPs you are most sensitive to and how much of them you can tolerate. This personalized approach is crucial for building a sustainable, long-term diet that is less restrictive.

The Elemental Diet

For more severe cases of SIBO, or for individuals who do not respond to antibiotics, the elemental diet is sometimes used. This is a nutritionally complete, liquid-only formula that provides nutrients in their simplest, predigested form (amino acids, simple sugars, fatty acids). Because the nutrients are rapidly absorbed in the upper small intestine, they do not reach the lower small intestine to feed the bacteria, effectively starving them. This diet must be followed under strict medical supervision due to its restrictive nature and should not be attempted on your own.

The Specific Carbohydrate Diet (SCD)

The Specific Carbohydrate Diet is a grain-free, sugar-free, and starch-free diet that has been used for inflammatory bowel conditions and is sometimes adapted for SIBO management. It is a more restrictive diet than the low-FODMAP approach but can also be effective at reducing bacterial food sources.

Foods to Include in a SIBO-Friendly Diet

Proteins: Lean meats (chicken, turkey), fish, eggs.
Fats: Olive oil, coconut oil, and small amounts of butter.
Grains (Low-FODMAP/SCD-friendly): Rice, quinoa, oats (cooked), and gluten-free crackers.
Vegetables (Low-FODMAP): Leafy greens (spinach, kale), carrots, zucchini, cucumbers, and bell peppers.
Fruits (Low-FODMAP): Strawberries, grapes, oranges, blueberries, ripe bananas.
Nuts and Seeds (Low-FODMAP): Walnuts, pumpkin seeds, and limited portions of other nuts.

Comparison of Common SIBO Diets


Feature	Low-FODMAP Diet	Elemental Diet	Specific Carbohydrate Diet (SCD)
Mechanism	Limits fermentable carbohydrates to reduce bacterial food.	Provides predigested nutrients, starving bacteria completely.	Excludes complex carbs, grains, and lactose.
Foods Allowed	Low-FODMAP fruits, vegetables, grains, proteins, fats.	Liquid formula only (powder mixed with water).	Meats, eggs, fruits, non-starchy vegetables, nuts, honey.
Foods Excluded	High-FODMAP foods (onions, garlic, beans, certain fruits).	All solid foods and non-formula beverages.	Grains, starches, lactose, most sugars.
Duration	2-6 week elimination phase followed by reintroduction.	Typically 2-3 weeks, strictly monitored.	Can be long-term, but often modified after symptom improvement.
Key Benefit	Symptom relief by reducing bacterial fuel through specific carb restriction.	Most effective at eliminating bacterial overgrowth during treatment.	Starves bacteria by removing common fermentable starches and sugars.
Key Consideration	Requires careful reintroduction to determine personal triggers.	Very restrictive, expensive, and requires medical supervision.	Can be very challenging and restrictive to follow long-term.

Beyond Diet: Additional Strategies for SIBO Management

In addition to dietary modifications, several other factors can influence SIBO symptoms and recovery.

Mindful Eating: Eating meals at regular intervals (every 3-4 hours) rather than continuous snacking is often recommended to support the Migrating Motor Complex, a “housecleaning” wave in the intestines. Chewing your food thoroughly also aids digestion.

Stress Reduction: Chronic stress negatively impacts gut health and can exacerbate SIBO symptoms. Incorporating relaxation techniques like meditation, yoga, or deep breathing can be beneficial.

Hydration: Staying well-hydrated is crucial for healthy digestion and can help with motility. Focus on non-carbonated, quality water throughout the day while limiting sugary drinks, alcohol, and excessive caffeine.

Supplements: Some nutritional deficiencies can arise from the malabsorption caused by SIBO, so a multivitamin may be helpful. Probiotics are a complex topic in SIBO; some can worsen symptoms, while specific strains may be beneficial, so they should be used with caution and professional guidance.

Conclusion: Personalizing Your SIBO Diet

Navigating the diet for small bowel overgrowth is a highly individualized process. While strategies like the low-FODMAP diet provide a strong framework for reducing bacterial fermentation and alleviating symptoms, there is no single, universally effective SIBO diet. Working with a healthcare provider or a registered dietitian is essential to identify the root cause of your SIBO and to create a tailored dietary and lifestyle plan. By understanding which foods fuel your symptoms and which ones support your recovery, you can effectively manage SIBO and take significant steps toward restoring your digestive health.

[Disclaimer: This article is for informational purposes only and does not constitute medical advice. Consult a healthcare professional for a personalized SIBO treatment plan.]

Frequently Asked Questions

The most widely used dietary approach is the low-FODMAP diet, which helps reduce the fermentable carbohydrates that feed overgrown bacteria and trigger symptoms. However, the best diet is highly individual and should be customized based on a patient's specific triggers and symptoms.

Probiotics should be used with caution and under professional guidance for SIBO. Some studies show potential benefits, while others raise concerns that probiotics could worsen the condition. In some cases, temporary discontinuation is advised.

No, a diet cannot cure SIBO but is a powerful tool for managing symptoms and supporting treatment, which often includes antibiotics or other therapies. Restrictive diets are not meant for long-term use and can even harm healthy gut bacteria if overused.

An elemental diet is a liquid-only diet of predigested nutrients that are quickly absorbed in the upper small intestine, effectively starving the bacteria. It is a proven treatment method for severe SIBO, but it is expensive, restrictive, and must be medically supervised.

You should generally avoid high-FODMAP foods like garlic, onions, apples, pears, beans, and certain dairy products, as well as processed sugars, and alcohol. Other personal triggers may also need to be identified through elimination.

The initial, more restrictive phase of a SIBO diet, like the low-FODMAP diet, is typically followed for two to six weeks. After that, a structured reintroduction phase helps personalize a less restrictive, long-term plan.

Stress can significantly worsen SIBO symptoms by negatively impacting gut health. Incorporating stress-reduction techniques like yoga or meditation is an important, non-dietary component of managing the condition effectively.